Fabrication of Flexible Integrated Circuits with FDSOI on Plastic Substrate for CMOS Image Sensors

We report the fabrication of flexible integrated circuits (ICs) for complementary metal-oxide semiconductor image sensors by using the layer transfer process of fully depleted silicon-on-insulator (FDSOI) circuits onto a plastic substrate. Our device combines the high performance of single crystalline silicon metal-oxide-semiconductor field-effect transistors (MOSFETs) and the flexibility of plastic. A 6-μm thick FDSOI device with 50-nm thick MOSFET active layers and aluminum wires is successfully transferred to a polyethylene terephthalate substrate. In addition to mechanical flexibility, operation of ICs including MOSFETs and 101-stage ring oscillators is confirmed, which demonstrates their potential in flexible highly integrated devices, such as image sensors and displays.